Spark gap adjusting pliers



March 2, 1954 w, CLARK 2,670,643

SPARK GAP ADJUSTING PLIERS Filed NOV- 3, 1952 1.5.) l U U U U 5 l FIG.2

INVENTOR. WILLIAM H. CLARK ATTOR NEY Patented Mar. 2, 195 4 UNITED STATES PATENT OFFICE SPARK GAP ADJUSTING PLIERS William H. Clark, near Silvis, 111.

Application November 3, 1952, Serial No. 318,403

2 Claims. 1

The present invention relates to tools for set ting the spark gap of spark plugs of motor vehicles and has, for its main object, the setting of the spark plug gap quickly and accurately.

In the drawings annexed hereto and forming a part hereof,

Fig. 1 is a side elevation of this tool applied to a spark plug in gap-setting position;

Fig. 2 is a plan view of the structure shown in Fig. 1; and

Fig. 3 is a fragmentary section, substantially along the plane indicated by the line 33, in Fig. 1, showing the head of the tool.

Essentially, this tool is a pair of pliers with a plurality of strips of metal called shims pivoted to be swung laterally into position for measuring the gap.

These pliers comprise a pair of handles I and 2 having jaws 3 and 4, the former of which is curved toward the latter, and the latter is provided with a notch 5 which has screw threads fitting the threads of the spark plug. The shims 6, I, 8, and 9 are marked, respectively 25, 30, 35, and 40, indicating .025, .030, .035, and .040 of an inch as the distance between the electrodes of the spark plug, and held in place by securing means, such as screws.

The shims are turned laterally so that the selected one will be in place, as shown in Fig. 3. The electrodes l0 and II, if they are not at the selected distance, will be too far or not far enough for the shim to go in between them. By having the electrode l0 touching the shim 6 and then, by pressing on the handles I and 2, said handles are brought together and the electrode l I is bent into position so that it is at the prescribed distance from the electrode l0, and then the electrodes for an engine will be exactly the same distance apart in each spark plug.

It will of course be understood that variations may be made in the structure described without departing from the spirit of this invention as dis- 2 closed in this specification and as defined in the appended claims.

Having now described my invention, I claim:

1. Means for adjusting the air gap between the outer and the central electrodes of a spark plug, comprising a pair of interfitting integral jaws with crossed handles pivotally secured together, one jaw having a forwardly opening notch provided on its inner surface with screw threads, a plurality of shims of varying thickness secured by a screw to said one jaw in close proximity to said notch, the other jaw having a curved end arched over said screw, said shims being positioned between the jaws for insertion between the electrodes of a spark plug in which the gap is to be adjusted, the said other jaw being engageable with the outer electrode and pressing said outer electrode against the shim, and the shim against the central electrode upon movement of the handles toward each other.

2. Pliers comprising a pair of pivotally interconnected levers with cooperating jaws extending from one side of the pivot, one jaw having a widened head provided with a forwardly opening notch which has screw threads in the inner surface thereof, a narrow plate secured to said jaw on the side toward the other jaw and extending over the notch, and securing means for securing the plate to the jaw, the other jaw being arched to bear against the narrow plate.

WILLIAM H. CLARK.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 764,212 Starbuck July 5, 1904 1,384,209 OToole July 12, 1921 1,435,150 Carpenter Nov. 14, 1922 1,439,664 Foehl Dec. 19, 1922 2,492,380 Duma Dec. 27, 1949 2,549,165 Brackenbury et al. Apr. 17, 1951 

